The clinical and immunologic responses of patients with insect sting anaphylaxis will continue to be monitored and correlated. Clinical results will be evaluated by the effects of inadvertent stings or planned stings under observation. Venom-specific IgE and IgG will be measured in sequential serum samples. The effects of time alone and of specific venom immunotherapy will be determined. Specific problems to be addressed include mechanisms of insect sting allergy and immunity, amount and duration of immunotherapy, and the natural history of insect sensitivity. Similar clinical and immunologic data will be applied to continuing studies of the natural history of large local reactions from insect stings and indications, if any, for specific venom immunotherapy. Yellow jacket, yellow hornet and Polistes venoms will be fractionated in order to isolate and identify antigenic and allergenic components. These fractions and the bald-faced hornet fractions already isolated, will be used for studies of the crossantigenicity and crossallergenicity of vespid venoms. More extensive studies of the allergenic relationship between honeybee and vespid venoms will be carried out using sera containing IgE antibodies reacting with both venoms.